The present invention concerns a pharmaceutical composition for treating hypertension. The components are L-.alpha.-methyl-3,4-dihydroxyphenylanine and salicylamide phenylglyoxal or L-ascorbic acid.
L-.alpha.-methyl-3,4-dihydroxyphenylalanine (.alpha.-methyldopa) is a commercial antihypertensive agent [see Merck Index 9th Ed., Item 5925 (1976)]. Salicylamide is a commercial analgesic [Merck Index 9th Ed., Item 8080 (1976)]. Phenylglyoxal apparently has no commercial pharmaceutical utility. L-ascorbic acid is a vitamin.
The combination of methyldopa with salicylamide phenylglyoxal or L-ascorbic acid has been found to have enhanced antihypertensive properties.